Calculation Given the Data

Question

Substance ∆Hof (kJ/mol)

CO2 (g) -393.5

H2O(g) -285.8

C4H10 (g) -124.7

calculate the ∆Horxn for the following reaction.

2C4H10 (g) + 13O2 (g) →8CO2 (g) + 10H2O (g)

Answer 1

∑products - ∑reactants

[(8x-393.5)+(10x-285.8)] - [(2x-124.7)+(13x0)]

[(-3148) + (-2858)] - (-249.4)

-6006 + 249.4 = -5757 kJ (to 4 sig.figs.) (check the math)